package com.jiang.mail;


import com.rabbitmq.client.Channel;
import com.xxxx.server.pojo.Employee;
import com.xxxx.server.pojo.MailConstants;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.amqp.support.AmqpHeaders;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.mail.MailProperties;
import org.springframework.data.redis.core.HashOperations;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.mail.javamail.JavaMailSender;
import org.springframework.mail.javamail.MimeMessageHelper;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageHeaders;
import org.springframework.stereotype.Component;
import org.thymeleaf.TemplateEngine;
import org.thymeleaf.context.Context;

import javax.mail.internet.MimeMessage;

import java.io.IOException;
import java.util.Date;

/**
 * 消息接收者
 */
@Component
public class MailReceiver {
    private static final Logger log= LoggerFactory.getLogger(MailReceiver.class);

    @Autowired
    private JavaMailSender javaMailSender;
    @Autowired
    private MailProperties mailProperties;
    @Autowired
    private TemplateEngine templateEngine;
    @Autowired
    private RedisTemplate redisTemplate;

    //消息幂等性操作，将接收人员改为接收消息和信道Employee employee
    @RabbitListener(queues= MailConstants.MAIL_QUEUE_NAME)
    public void handler(Message message, Channel channel) throws IOException {
        //通过消息拿到员工类
        Employee employee=(Employee) message.getPayload();
        //通过消息拿到请求头
        MessageHeaders headers = message.getHeaders();
        //根据消息头拿到消息序号
        Long tag=(Long)headers.get(AmqpHeaders.DELIVERY_TAG);
        String msgId=(String) headers.get("spring_returned_message_correlation");
        HashOperations hashOperations=redisTemplate.opsForHash();
        //如果消息被消费过，直接返回
        try{
            if(hashOperations.entries("mail_log").containsKey(msgId)){
                log.info("消息已经被消费=========>{}",msgId);
                /**
                 * 手动确认消息
                 * tag：消息序号
                 * multiple：是否确认多条
                 */
                channel.basicAck(tag,false);
                return;
            }
            MimeMessage msg=javaMailSender.createMimeMessage();
            MimeMessageHelper helper=new MimeMessageHelper(msg);
            //发件人
            helper.setFrom(mailProperties.getUsername());
            //收件人
            helper.setTo(employee.getEmail());
            //主题
            helper.setSubject("入职欢迎邮件");
            //发送日期
            helper.setSentDate(new Date());
            //邮件内容
            Context context=new Context();
            context.setVariable("name",employee.getName());
            context.setVariable("posName",employee.getPosition().getName());
            context.setVariable("joblevelName",employee.getJoblevel().getName());
            context.setVariable("departmentName",employee.getDepartment().getName());
            String mail=templateEngine.process("mail",context);
            helper.setText(mail,true);
            //发送邮件
            javaMailSender.send(msg);
            log.info("邮件发送成功");
            //将消息存入redis
            hashOperations.put("mail_log",msgId,"ok");;
            //手动确然消息
            channel.basicAck(tag,false);
        }catch(Exception e){
            //若是再发送消息,和存入redis的消息匹配结果一致，打印错误消息
            /**
             *手动确认消息
             * tag：消息序号
             * multiple: 是否确认多条
             * requeue: 是否返回队列
             */
            try {
                channel.basicNack(tag,false,true);
            } catch (IOException ex) {
                log.error("消息确认失败=====>{}", ex.getMessage());
            }
            log.error("邮件发送失败========>{}",e.getMessage());
        }




    }
}
